Hard-surface disinfection system

ABSTRACT

UV hard-surface disinfection system that is able to disinfect the hard surfaces in a room, while minimizing missed areas due to shadows by providing multiple UV light towers that can be placed in several areas of a room such that shadowed areas are eliminated and that can be transported by a cart that is low to the ground such that the towers may be loaded and unloaded easily by a single operator. The system is able to be controlled remotely, such that during activation of the system, no operator is present, and to automatically cut power to all towers in the event that a person enters the room.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/018,440 filed Feb. 8, 2016 entitled Hard-Surface Disinfection System,which is a continuation of U.S. patent application Ser. No. 14/540,869filed Nov. 13, 2014 entitled Hard-Surface Disinfection System, which isa continuation of U.S. patent application Ser. No. 14/043,465 filed Oct.1, 2013 entitled Hard-Surface Disinfection System, which is acontinuation of U.S. patent application Ser. No. 12/963,590 filed Dec.8, 2010 entitled Hard-Surface Disinfection System (now U.S. Pat. No.8,575,567 issued Nov. 5, 2013), which is the non-provisional of andclaims priority to U.S. Provisional Application Ser. No. 61/324,257filed Apr. 14, 2010, entitled Hard-Surface Disinfection System and toU.S. Provisional Application Ser. No. 61/267,805 filed Dec. 8, 2009,entitled Hard-Surface Disinfection System, the contents of all of whichare incorporated herein in their entireties.

FIELD OF THE INVENTION

The present invention relates to systems for disinfection ofhard-surfaces and related methods thereof and, more particularly, toultraviolet light disinfection of hard-surfaces.

BACKGROUND OF THE INVENTION

Disinfection of the hard surface environment is a key factor in theconstant battle to reduce infections. The emergence of multi-drugresistant organisms (MDROs) throughout the as-built environment poses asignificant threat to the health and well-being of people throughout theworld. MDROs in the environment contribute to rising health care costs,excessive antibiotic use and premature mortality.

Disinfecting hard surfaces, such as those found in patient areas, can beperformed by exposing the hard surfaces to UVC light that is harmful tomicro-organisms such as bacteria, viruses and fungi. Ultravioletgermicidal irradiation (UVGI) is an evidence-based sterilization methodthat uses ultraviolet (UV) light at sufficiently short wavelengths tobreak-down and eradicate these organisms. It is believed that the shortwavelength radiation destroys organisms at a micro-organic level. It isalso believed that UV light works by destroying the nucleic acids inthese organisms, thereby causing a disruption in the organisms' DNA.Once the DNA (or RNA) chain is disrupted, the organisms are unable tocause infection. The primary mechanism of inactivation by UV is thecreation of pyrimidine dimers which are bonds formed between adjacentpairs of thymine or cytosine pyrimidines on the same DNA or RNA strand.

There are several advantages to utilizing UV light, in addition to theeffectiveness described above. UV light requires only electricity, thereare no potentially hazardous chemicals and the associated storagechallenges presented thereby. UV light leaves no residue, does notrequire drying time, cannot be spilled, requires little manpower toapply, requires very little skill on the part of the operator, and useslong-lasting bulbs that require very little inventory management.

Safely using UV light to disinfect hard surfaces does present someunique problems. First, UV light sources cast shadows. Areas in shadowsmay not get disinfected. Second, UV light bulbs, like nearly all lightbulbs, are relatively fragile and present dangers if broken. Third, UVradiation is harmful to humans, especially in high-intensityapplications like those used in disinfecting procedures.

As such, there is a need for a UV hard-surface disinfection system thatexploits the advantages of UV light, while also addressing theaforementioned problems.

SUMMARY OF THE INVENTION

One aspect of the present invention provides a UV hard-surfacedisinfection system that is able to disinfect the hard surfaces in aroom, while minimizing missed areas due to shadows. In one embodiment, asystem is provided that includes multiple UV light towers. These towerscan be placed in several areas of a room such that nearly all shadowedareas are eliminated.

Another aspect of the present invention provides a UV light tower designthat incorporates a robustly protected light bulb, thus reducing theoccurrence of broken bulbs. In one embodiment, the tower comprises avertically oriented light bulb surrounded by a plurality, preferablythree, protective blades running the length thereof. The bladespreferably radiate from the bulb and are spaced 120 degrees apart. Thisdesign provides significant protection to the bulb, while minimizinginterference with the light being emitted from the bulb.

In another preferred embodiment, the light bulb is surrounded andprotected by a clear, quartz sleeve. In addition to protecting the bulbfrom accidental breakage, the sleeve induces a convection effect, like achimney. As the bulb heats, cool air is drawn through vents in thebottom of the sleeve, heated and exhausted through the top of thesleeve. This circulation cools the bulbs, extending their life andprotecting users from accidental burns.

In order to further protect the bulb, another aspect of the presentinvention provides a tower that has a relatively wide base and a verylow center of gravity. This design is a safety feature that createsstability and reduces the possibility of a tower tipping over while itis being moved.

In yet another aspect of the present invention there is provided a UVdisinfection system that minimizes UV light exposure to humans duringoperation. In a preferred embodiment, the system is able to becontrolled remotely, such that during activation of the system, nooperator is present in the room.

In another preferred embodiment, one or all towers are outfitted withsafety devices that cut power to all towers in the event that a personenters the room. More preferably, the safety device includesmotion-detecting capability, such that the safety shutdown response isautomatic. In a preferred embodiment, the motion detection capabilityincorporates a laser scanner, providing an extremely accurate motiondetection capability that is more thorough and less prone to falsepositives than other motion detection scanners such as infra-reddevices.

Another aspect of the present invention provides a control cart that isconstructed and arranged to transport a plurality of towers. The cart islow to the ground such that the towers may be loaded and unloaded easilyby a single operator. Alternatively, the towers may be linked togetherwith the cart to form a chain. This embodiment allows the towers tosupport themselves continuously, while being transported by pushing orpulling the cart. This embodiment also allows the use of a hand-cartattachment, which provides a solution to moving all of the units fromone room to another without requiring that they be reloaded onto thecontrol cart, which may be left in a single location, such as a hallway,in proximity to both rooms.

One embodiment provides a cart that includes a control panel that can beused to remotely control various parameters of each of the towers, aswell as provide various diagnostic data to the user.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an embodiment of a system of the presentinvention;

FIG. 2 is a perspective view of an embodiment of a system of the presentinvention;

FIG. 3 is a perspective view of an embodiment of a light tower of thepresent invention;

FIG. 4 is a perspective view of an embodiment of a light tower of thepresent invention in a first configuration;

FIG. 5 is a perspective view of the light tower of FIG. 5 in a secondconfiguration;

FIG. 6 is a perspective view of an embodiment of a base of a light towerof the present invention;

FIG. 7 is a perspective view of an embodiment of a base of a light towerof the present invention;

FIG. 8 is a perspective view of an embodiment of a light tower of thepresent invention connected to two other light towers and a hand cart ofthe present invention;

FIG. 9 is a bottom perspective view of an embodiment of a light tower ofthe present invention loaded into a controller cart with two other lighttowers;

FIG. 10 is a partial elevation view showing an embodiment of a tower capof a light tower of the present invention; and

FIG. 11 is a partial elevation view showing an embodiment of a tower capof a light tower of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Specific embodiments of the invention will now be described withreference to the accompanying drawings. This invention may, however, beembodied in many different forms and should not be construed as limitedto the embodiments set forth herein; rather, these embodiments areprovided so that this disclosure will be thorough and complete, and willfully convey the scope of the invention to those skilled in the art. Theterminology used in the detailed description of the embodimentsillustrated in the accompanying drawings is not intended to be limitingof the invention. In the drawings, like numbers refer to like elements.

Referring now to the figures and first to FIG. 1, there is shown anembodiment of a system 10 of the present invention. System 10 generallyincludes a control station or cart 100 and a plurality of lightassemblies or towers 200, shown as loaded onto the cart 100.

The cart 100 generally includes a carriage 110 supported by a pluralityof casters 112, and defining a cutout 114 shaped to receive and securethe towers 200 for transport. The distal end 116 of the cutout 114 isopen such that the towers may be easily loaded onto and off of the cart100. The cutout 114 may include a complete floor (not shown) onto whichwheels 202 of the towers 200 (see FIG. 2) may be rolled.

More preferably, however, the cutout 114 has an open bottom and asupporting ridge that slightly elevates the wheels 202 off the ground.This design provides a secure relationship between the cart 100 and thetowers 200. Many hospitals include ramped areas. Disabling the wheels202 by elevating the towers 200 prevents the towers from rolling off ofthe cart 100.

Alternatively, as shown in FIG. 2, an embodiment 101 of the cart has acarriage 111 that allows the towers 200 to remain in contact with theground, rather than being elevated. The towers in this embodiment arepreferably linked together for transport, with at least one tower beinglinked or otherwise attached to the cart 100.

The cart 100 or 101 may also include a pair of safety arms 120 thatextend along the length of the cart 100 or 101 on other side of thetowers 200 when the towers 200 are loaded onto the cart 100 or 101.Aesthetically, the arms may match the cutout 114 of the carriage 110 or111. Functionally, the arms 120 provide protection against accidentallyimpacting the towers against objects or people as the towers 200 arebeing transported on the cart 100 or 101.

In one embodiment, at a proximal end 122 of the cart 100, there is afoot jack 126. The foot jack 126 is usable to elevate the cart 100enough to raise the wheels 202 off the ground. In this way, the wheels202 of the towers 200 may be used to roll the towers 200 into the cutout114. Once the towers 200 are in place within the cutout 114, the footjack 126 is depressed, raising the towers 200 off the ground. When it isdesired to deploy the towers 200, the foot jack 126 is released and thecart 100 lowers the towers 200 such that the wheels 202 are again incontact with the ground.

Also at the proximal end 122 of the cart 100 or 101, there is a handle130 and a control panel 140. The control panel 140 may include a display142 usable to display a variety of parameters relevant to the safeoperation of the towers 200. The parameters include, but are not limitedto: ambient room temperature, room dimensions, fluence level,disinfection time, input current and voltage, and maintenanceinformation such as bulb run time. Additionally, the control panel maybe used to upload, preferably wirelessly, data to a hospital informationsystem regarding the sanitization of a given room. It is also envisionedthat the control panel would have a communications ability that iscompatible with the LMS (or similar) system found in many hospitals(smart scanner system to evaluate distance and occupancy) e.g. the LMScan map the room and an algorithm could calculate emitter run times.

One embodiment of a light tower 200 is shown in FIG. 3. The light tower200 generally includes a base 220 supported by a plurality of wheels202, a tower assembly 250, and a cap 300.

Another embodiment of a light tower 201 is shown in FIG. 4. The lighttower 201 includes a base 221 and is supported by a plurality of wheels202, a tower assembly 251, and a cap 301, but also has a push ring 400assembly for use in moving the light tower 201 without applying pressureto the light source 270. The push ring 400 preferably includes a handle410 and a plurality of telescoping supports 420. The telescopingsupports 420 allow the push ring to be stowed in an activeconfiguration, shown in FIG. 5, when the light source 270 is activated.Because the push ring 400 is lowered in the active position, it does notinterfere with the light beams emitted by the light source 270, therebyensuring no shadows are created by the push ring assembly.

Electronics may be utilized to prevent the activation of the lightsource, and/or emit a warning, if the push ring is in the up position.Alternatively, the telescoping arms 420 may be automatically activatedsuch that they lower themselves prior to activating the light source andraise themselves upon completion.

Reference is now made to FIGS. 6-9, which show details of embodiments220 and 221 of the base, respectively. Notably, shared features betweenthe two are indicated by common reference numerals. It is alsounderstood that in these Figures, and throughout the specification, thatfeatures may be interchangeable between embodiments. The base 220 or 221is comprised of a housing 222 or 223 that contains power circuitry forthe tower 200 or 201. Preferably, the housing 222 or 223 is round sothat the tower 200 or 201 may be easily docked within the cart 100 or101 without regard to angular orientation. The housing 222 or 223 mayoptionally include one or more bumpers 224 (shown associated withhousing 222) to protect the base 220 or 221 as well as anything the base220 or 221 may contact.

The base 220 or 221 may also include one or more power connections 226.Providing a plurality of power connections 226 allows one of the towers200 or 201 (designated herein as the “master” tower) to be connectedinto a standard outlet. The remaining towers may then be “daisy-chained”to the master such that power to all of the towers 200 or 201 may becontrolled by the cart 100 or 101. This results in a redundant safetyrelay in the base 220 or 221 of the master to control power to alldown-stream units that are connected together. The power connections 226are shown in the Figures as being female outlets but one skilled in theart will realize that this is merely a convention of convenience and notto be interpreted as limiting.

The tower assembly 250 generally includes a base connector assembly 260,a light source 270, and, optionally, a plurality of protective blades280. The base connector assembly 260 connects the bottom of the towerassembly 250 to the base 220 or 221. The base connector assembly 260includes one or more connectors 262, shown in FIG. 6 in non-limitingexample as hand screws, and in FIG. 7 in non-limiting example as boltsor machine screws, and a light socket 264. Preferably, the connectors262 may be secured and released without the use of tools for ease ofbulb replacement and other maintenance. Most importantly, the lightsocket 264 securely connects the tower assembly 250 to the base 220 andis sturdy enough to withstand lateral forces placed on the towerassembly 250.

The light source 270 may be any appropriately shaped UV light source,capable of emitting sufficient light for purposes of sanitizing a room.Non-limiting examples include a low pressure amalgam light source,preferably with a solarization-reducing coating. Foreseeably, an LED UVlight source would draw less power and may be optimally suited tobattery-powered towers 200. The light source 270 preferably includes avariable output transformer 271 (see FIG. 7). The variable outputtransformer 271 controls the output power of the light source 270.

As shown in FIG. 7, the base 220 or 221 may also include a fluencysensor 273. This sensor 273 monitors the power output of the lightsource 270 to ensure that it maintains an output over a threshold, whichmay be either an absolute threshold, or a range within a set poweroutput. If the light source 270 has a power output that drops below thisthreshold, the sensor 273 sends a signal to the control panel 140indicating a lower power output status of a given tower 200 or 201. Thismay indicate a bad bulb or other problem that may result in compromiseddisinfection if the condition is not repaired.

Also shown in FIG. 7 is a lockout disconnect 275. This is a mechanicalpower switch that accommodates a padlock that, when in place, preventsthe power switch from being turned to an on position. This ensures atower 200 or 201 may not be inadvertently activated.

Shown also in FIG. 7 is a mechanical linkage 277 that allows the base221 to be mated with another base 221. The linkage 277 is a femalelinkage. A corresponding male linkage 279 is on the other side of thebase 201. As discussed above, these linkages 277 and 279 provide aconvenient means for transporting the towers 200 or 201 from room toroom. FIG. 8 shows three towers 201 connected together with linkages 277and 279 and a handle 281 configured to mate with a male connector 279 ora female connector 277.

FIG. 9 shows an embodiment of a bottom of base 220 or 221 that includesone or more floor lamps 283. The floor lamps 283 provide disinfectinglight under the bases 220 or 221 to ensure there are no shadows createdby the units themselves, and also that contaminants are not dragged fromroom to room by the towers 200 or 201.

Though the light source 270 is shown as being vertically-oriented, it isenvisioned that the light source 270 may be angled or even oscillatingto further reduce shadows.

The selection of a lamp is a significant factor in determining thefootprint of the system 10. The physical layout of a patient care areawill provide obstacles to the UVC emissions. These obstacles willproduce shadows on surfaces and therefore reduce the effectiveness ofthe system in certain areas of the patient care area. The system 10footprint is flexible so that it can be deployed in such a way toovercome these shadows. Satellite rooms such as the washroom attached toa patient care area will also pose a challenge to the system as theseareas have a high probability of containing micro-organisms that couldlead to a Hospital Acquired Infection. The UVC reflective properties ofmaterials are not the same as that of visible light. The systems will bedeployed in existing patient care areas so selection of materials with ahigh degree of UVC reflectivity is not an option. The system'srepeatability will suffer if system depends on reflected UVC light toovercome shadows from obstacles in the room.

The light source 270 is preferably surrounded by a protective sleeve272. The protective sleeve may be constructed of any suitable clearmaterial capable and very efficient at passing UVC as well as protectingthe bulb against impact without significantly interfering with the lightbeing emitted.

In a preferred embodiment the protective sleeve 272 comprises a quartzsleeve, synthetic quartz sleeve or similar synthetic material to providestability to the bulb as to not restrict light and/or create shadow. Ithas been noted that using a quartz sleeve 272 creates a protectivetemperature barrier to reduce the severity and/or occurrence of skinburns. Because the sleeve 272 is significantly cooler than the bulbsurface, using a sleeve 272 may also reduce odors due to dust and otherparticulates landing on the bulb and burning.

It is known that the sleeve 272 creates a chimney effect in that heatcoming off the light source 270 rises forcing cool convection air to bedrawn upward through the sleeve 272 from the bottom. It may bebeneficial to provide a forced cooling system, in which a fan could beprovided in-line with the top or bottom of the sleeve 272.

In most applications, the quartz sleeves 272 provide sufficientprotection against accidental breakage. However, some applications maywarrant a more robust design. As such, one embodiment of the presentinvention provides a light source 270 that further includes a plurality,preferably three, protective blades 280 radiating from the light source270 (e.g. FIG. 3) or guidewires 281 (e.g. FIG. 5). The blades orguidewires 280 or 281 may be any acceptably light, yet strong material,such as aluminum, plexiglass, or the like. A clear material may reduceshadows but, due to the thin construction and radiating orientation ofthe blades 280, they have very little effect on the light emissioncapabilities of the light source 270. Shown are three blades 280, spaced120 degrees apart, and including a plurality of circular cutouts used toincrease stiffness and reduce weight, or four guidewires 281 space 90degrees apart.

Referring now to FIGS. 10 and 11, there are shown two embodiments 300and 301 of the cap assembly at the top of the tower assembly 250. Thecap assembly 300 or 301 is used to secure the various components of thetower assembly 250 together. The cap assembly 300 or 301 also preferablyhouses a safety sensor 302 or 303, preferably a motion detector thatsenses if a person has entered a room and disables the tower. Thismotion detector could be an infrared motion detector, such as thosefound in many security systems, or it could be a dual motion detector, adoor curtain or the like. Preferably, the safety sensor 302 or 303includes a motion detector that uses lasers that scan the surroundingarea. A preferred embodiment of the cap assembly 301, shown in FIG. 11,utilizes a safety sensor 303 that overhangs the rest of the cap assembly301 such that the sensor can “see” virtually straight down, giving thesensor nearly 180 degrees of vertical coverage, as well as 360 degreesof coverage in a horizontal plane. As such, safety sensor 303 has nearlycomplete spherical coverage with exception of the area directly underthe base, which would not encounter motion.

In a preferred embodiment, the cap assembly 300 or 301, or the baseassembly 220 or 221, also includes a communications module 304. Thecommunications module 304 communicates via any acceptable medium such asradio, wifi, microwaves, Bluetooth®, etc., with the cart 100 or 101, andoptionally the other towers 200 or 201. Thus, if one sensor 302 or 303senses movement, a signal could be sent to the other towers 200 or 201to shut down. Alternatively, a signal could be sent to the cart 100 or101, which would in turn shut the remaining towers 200 or 201 down.

The sensor 302 or 303 may also be used to detect and monitor the fluencelevel of the UV emissions (unless the base includes a fluence sensorsuch as the fluence sensor 273 on base 221) to confirm that the tower200 or 201 is operating at a desired level. These sensors can be used inconjunction with an amplifier to transmit the data to a control devicethat will integrate the irradiance level to obtain the fluence levelreceived at the sensor. Single point photosensors are sensitive to theangle of light incidence.

Preferably, the tower 200 or 201 also includes a speaker (not shown) ineither the communications module 304 or the base 220 or 221 that createsan audible warning before the light source 270 is energized. It is alsoenvisioned that the communications module 304, may be used toelectronically measure the room to determine the appropriate outputnecessary by the tower 200 to adequately sanitize the space. Thisfeature ensures that energy is not wasted and bulb life and safety aremaximized.

The cap assembly 301 shown in FIG. 11 also includes one or more vents305 in fluid communication with an interior of the protective sleeve 272to allow air heated by the lamp 270 to escape.

Although the invention has been described in terms of particularembodiments and applications, one of ordinary skill in the art, in lightof this teaching, can generate additional embodiments and modificationswithout departing from the spirit of or exceeding the scope of theclaimed invention. For example, the system of the present inventionmight be well-suited for applications outside of healthcare.Non-limiting examples include locker rooms and other athleticfacilities, daycares, prisons etc. Accordingly, it is to be understoodthat the drawings and descriptions herein are proffered by way ofexample to facilitate comprehension of the invention and should not beconstrued to limit the scope thereof.

What is claimed is:
 1. A disinfection system comprising: a plurality ofindependently placeable energy emitter assemblies, each of theassemblies including: a base; an elongate energy emitter extendingvertically from said base; a communications module; a controller in datacommunication with each of the communications modules of the pluralityof energy emitter assemblies; wherein said controller is capable ofremotely controlling activation and deactivation of said plurality ofenergy emitter assemblies.
 2. The disinfection system of claim 1 whereinsaid base comprises a plurality of wheels extending downwardly from abottom of said base.
 3. The disinfection system of claim 1 wherein saidelongate energy emitter comprises a tower.
 4. The disinfection system ofclaim 1 further comprising a cap attached to a top of said energyemitter assembly.
 5. The disinfection system of claim 2 furthercomprising a push ring assembly extending from said base for use inconjunction with said wheels to move said energy emitter assembly oversurfaces without applying pressure to said elongate energy emitter. 6.The disinfection system of claim 5 wherein said push ring comprises ahandle and a plurality of supports.
 7. The disinfection system of claim6 wherein said plurality of supports comprises a plurality oftelescoping supports.
 8. The disinfection system of claim 1 wherein saidbase comprises a housing.
 9. The disinfection system of claim 8 whereinsaid housing contains power circuitry for said elongate energy emitter.10. The disinfection system of claim 4 wherein said cap comprises asafety feature capable of shutting off said plurality of independentlyplaceable light towers if movement is detected in said space.
 11. Amethod for disinfecting an enclosed space comprising: providing aplurality of independently placeable energy emitter assemblies each ofthe assemblies including: a base; an elongate energy emitter extendingvertically from said base a cap located on top of said elongate energyemitter; and, a communications module; positioning at least one of theplurality of independently placeable energy emitter assembliesthroughout an enclosed space; establishing data communication between acontroller and the at least one of the plurality of independentlyplaceable energy emitter assemblies; remotely energizing the at leastone of the plurality of independently placeable energy emitterassemblies; scanning said space for movement using a safety feature atleast partly located in said cap; shutting down said at least one of theplurality of independently placeable energy emitter assemblies if saidsafety feature detects movement in said space.
 12. The method of claim11 wherein the step of positioning at least one of the plurality ofindependently placeable energy emitter assemblies throughout an enclosedspace comprises determining a positioning of said at least one of theplurality of independently placeable energy emitter assemblies thatminimizes the creation of shadows.
 13. The method of claim 11 whereinsaid base comprises wheels and a handle and wherein the step ofpositioning at least one of the plurality of independently placeableenergy emitter assemblies throughout an enclosed space comprises pushingthe handle.
 14. The method of claim 11 wherein establishing datacommunication between a controller and the at least one of the pluralityof independently placeable energy emitter assemblies comprises employinga wireless network.
 15. A hard-surface disinfection system comprising: aplurality of independently placeable ultraviolet light emitting towers,each including a base and at least one ultraviolet light emitterextending vertically from said base; wherein each of the plurality ofindependently placeable ultraviolet light emitting towers is capable ofbeing controlled remotely by a common wireless controller; wherein eachof the bases comprises wheels and a handle.
 16. The hard-surfacedisinfection system of claim 15 further comprising connectors attachedto said bases constructed and arranged such that each of the bases maybe connected together, allowing the plurality of independently placeableultraviolet light emitting towers to be connected and rolled as a singleunit.
 17. The hard-surface disinfection system of claim 15 wherein eachof the plurality of independently placeable ultraviolet light emittingtowers further includes a cap attached to a top thereof and containing amotion detector.
 18. The hard-surface disinfection system of claim 17wherein each of the plurality of independently placeable ultravioletlight emitting towers comprises a communications module capable of atleast receiving data from a common wireless controller.
 19. Thehard-surface disinfection system of claim 17 wherein each of theplurality of independently placeable ultraviolet light emitting towerscomprises a communications module capable of sending data.
 20. Thehard-surface disinfection system of claim 17 wherein each of theplurality of independently placeable ultraviolet light emitting towerscomprises a communications module allowing each of said independentlyplaceable ultraviolet light emitting towers to communicate with eachother.